As is known, numerous techniques have been developed for dyeing and printing sheets. Dyes which have an affinity for their substrate, for example, can be directly applied from an aqueous dye bath or suitable organic solvent. Dyes which are insoluble or have no affinity with the substrate can in many cases be applied to the surface by means of a suitable binder, (for example vinyl polymers or copolymers, copolymers of maleic acid anhydride and ethylene, etc). Certain dyes which have no affinity for the substrate but are capable of sublimation can be applied to a substrate by sublimation.
Many fabrics, in particular cotton fabrics and sheets based on glass or asbestos fibers generally cannot be dyed or printed satisfactorily with the known techniques. The colors obtained are usually unstable and dissolve from the fiber, e.g. in washing.